Minion front...2.35 for trails (Ignitor 2.35 backup option), 2.5 (ST) for mountain stuff. Rear...Advantage or Ardent. Having said that, the cheaper option for the rear is Smorgasbord for trails, Chunky Monkey for mountain stuff

Hang on, he's after less drag not more. I'm still running the much-derided Crossmark on the rear (HR front for me) in the winter. It's fine most of the time, and certainly never slows me down. Every now and then I swap it for a Mud-X and then wish I hadn't.

There must be other slightly better options out there - Saguaro perhaps? Might try one when the Crossmark eventually wears out.

I run Maxxis Advantage 70A 2.1 front and rear the front grippy, very grippy just not in mud. But I find the rear drags a lot unless it's dry.

Not trying to be funny but by most folks' standard, the 70a advantage isn't an especially grippy tyre, and certainly not a draggy one. I honestly can't think of anything faster rolling that doesn't have major drawbacks.

I use a 2.35 Minion DHF Front 60a and then go for a Medusa 2.1 rear. Its a mud tyre but I use it all year round and its been good as gold, don't feel like I need extra rear grip or its draggy so its a win win for me

DHF 2.35 on the front, Advantage 2.2 on the back when I had 26inch wheel biked. Sadly can't get that combo on 29er. DHF 2.35 is now available thankfully which I run on the front and an Ardent 2.2 on the back of my FS29er. Good combo for all condition, ardent is a bit sketchy when it's really muddy and I'm not brave enough to run it on the front!

I loved Ignitors (2.25 LUSTs) but they were mildly terrifying in the FoD mud and again they don't do a decent 29er size.

Crossmark in winter is 'madness' in a fun sense of the word. If you know what to expect it can be great fun having the front end nailed to the ground with a grippy tyre whilst the back slews and skitters around. Really good fun for a 'play' ride. Long grassy or muddy climbs are no fun, though.

I may keep the advantage on the rear and run it with a High roller 2 as I really liked the High roller all round was just a bit stuffy on the back. I found Conti rubber queen run faster but I had a massive brown pant moment when the front let go never had that with my Advantages so I think I'd rather live with slightly slower rolling and not lose grip.

At the moment I'm running an ikon up front and a custom crossmark out back for xc racing at newnham and general riding on the quantocks. On the crossmark i chop off all the little round side knobs for a more aggressive cornering ability - still spins a bit on muddy climbs but I prefer less drag to grip - but does clear surprisingly well. The ikon does pack out a bit in claggy mud but is manageable.
Come summer I'll leave the crossmark on as it gets faster as it wears, and probably run an aspen on the front for dry or the ikon if it's a summer like 2-3 years ago. All 3 are decent big volume for low pressure.
When it's really claggy and sticky mud then medusa front and back